The density of a plastic part used in a cellular telephone is required to be at least 0.70 g/cm3. The parts are supplied in large lots, and a variables sampling plan is to be used to sentence the lots. It is desired to have p1 =0.02,p2 =0.10, α?=0.10, and β=0.05. The variability of the manufacturing process is unknown but will be estimated by the sample standard deviation.
(a) Find an appropriate variables sampling plan, using Procedure 1.
(b) Suppose that a sample of the appropriate size was taken, and=0.73 , s =1.05 ??10-2. Should the lot be accepted or rejected?
(c) Sketch the OC curve for this sampling plan. Find the probability of accepting lots that are 5% defective.